You have a binary string $a$ of length $n$ consisting only of digits $0$ and $1$.
You are given $q$ queries. In the $i$-th query, you are given two indices $l$ and $r$ such that $1 \le l \le r \le n$.
Let $s=a[l,r]$. You are allowed to do the following operation on $s$:
- Choose two indices
$x$and$y$such that$1 \le x \le y \le |s|$. Let$t$be the substring$t = s[x, y]$. Then for all$1 \le i \le |t| - 1$, the condition$t_i \neq t_{i+1}$has to hold. Note that$x = y$is always a valid substring. - Delete the substring
$s[x, y]$from$s$.
For each of the $q$ queries, find the minimum number of operations needed to make $s$ an empty string.
Note that for a string $s$, $s[l,r]$ denotes the subsegment $s_l,s_{l+1},\ldots,s_r$.
Input
The first line contains two integers $n$ and $q$ ($1 \le n, q \le 2 \cdot 10 ^ 5$) — the length of the binary string $a$ and the number of queries respectively.
The second line contains a binary string $a$ of length $n$ ($a_i \in \{0, 1\}$).
Each of the next $q$ lines contains two integers $l$ and $r$ ($1 \le l \le r \le n$) — representing the substring of each query.
Output
Print $q$ lines, the $i$-th line representing the minimum number of operations needed for the $i$-th query.
Note
In the first test case,
- The substring is
$\texttt{101}$, so we can do one operation to make the substring empty. - The substring is
$\texttt{11011}$, so we can do one operation on$s[2, 4]$to make$\texttt{11}$, then use two more operations to make the substring empty. - The substring is
$\texttt{011}$, so we can do one operation on$s[1, 2]$to make$\texttt{1}$, then use one more operation to make the substring empty.
样例
5 3
11011
2 4
1 5
3 5
1
3
2
10 3
1001110110
1 10
2 5
5 10
4
2
3
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